I just bought a 02 subaru wrx 5spd. about a month ago and ever since, i've been seeing a good bit of stuff about engine and transmission problems and failures, and then theres people that say they last forever. It really confuses me. I've read about engines that start knocking with 70 to 100k miles on them. Why is this? The car i bought has about 112k miles on it and it had another short block put in it about 6 months ago due to a bottom end knock.